AI & LLM Tools
Token counting, prompt builders, function schema generators, and other AI/LLM developer utilities.
AI Token Counter
Count GPT-4, Claude, and Gemini tokens with estimated API cost breakdown per model.
Use toolJSON to OpenAI Function Schema
Convert JSON objects or TypeScript interfaces to OpenAI function-calling / tool-use schemas.
Use toolSystem Prompt Builder
Build structured AI system prompts with sections for persona, tone, constraints, and output format.
Use toolAI Prompt Diff
Compare two AI prompts side by side and highlight exactly what changed between versions.
Use toolAbout AI & LLM Tools
Token counting, prompt builders, function schema generators, and other AI/LLM developer utilities.
Why Use These Tools?
All ai & llm tools on Devkitr are completely free and run 100% in your browser. Your data never leaves your device — there are no server-side requests, no data logging, and no sign-up required.
Privacy & Security
Every tool in this category processes your data entirely in your browser using JavaScript. We never transmit, store, or log any data you input. You can verify this by opening your browser's Developer Tools and monitoring the Network tab while using any tool — you'll see zero data requests related to your input.
Available Tools
- AI Token Counter – Count GPT-4, Claude, and Gemini tokens with estimated API cost breakdown per model.
- JSON to OpenAI Function Schema – Convert JSON objects or TypeScript interfaces to OpenAI function-calling / tool-use schemas.
- System Prompt Builder – Build structured AI system prompts with sections for persona, tone, constraints, and output format.
- AI Prompt Diff – Compare two AI prompts side by side and highlight exactly what changed between versions.